I believe a significant part of that issue is that for many of the promo photos they chose to have her looking slightly upward. That angle effectively squashes her features a bit and makes her head look much less angular than it should. But if you look at many of the shots of the prototype from the Vegas show, most of those photos were shot from above, and there you can see that her face has the proper shape.
I honestly don't know who is in charge of both the photography itself and also the photos that are chosen by EXO-6 as the ones to be featured on their site, but SO OFTEN those pictures do very little if anything to highlight and show the figures in their best light. I realize that many of those promo shots are of earlier prototypes that were the only figures available at the time the promo photos needed to be used for marketing, but even so, that fault is at least as much an issue of the photography itself. This needs to change, EXO...